Enhanced Adsorption of NiNb Bimetallic Catalyst for CO₂ Intermediates Facilitates the 100% Selective Dicarboxylation

The electrochemical carboxylation of alkenes with CO₂ is an effective route for the synthesis of high-value chemicals; however, achieving high yield and selectivity remains a significant challenge. In this study, we developed a nickel-niobium bimetallic catalyst (NiNb@NF) for the electrochemical carboxylation of conjugated dienes with CO₂. The catalyst exhibited optimal electrochemical carboxylation activity, achieving ∼100% selectivity for dicarboxylic acid products, with a high dicarboxylation yield of 96.4%. Electrochemical measurements demonstrated that the NiNb bimetallic catalyst maintained a stable substrate adsorption capacity under a CO₂ atmosphere. Mechanistic studies, including in situ infrared and Raman spectroscopy, revealed that the NiNb bimetallic catalyst possesses strong adsorption ability for CO₂ intermediates, which facilitates the dicarboxylation pathway and suppresses the formation of monocarboxylated byproducts. This work lays the foundation for the industrial application of this reaction and provides new insights into the design of efficient CO₂ conversion electrocatalytic materials.